JP2001326394A - Thermoelectric element module having electric insulating film - Google Patents

Abstract

(57) Abstract: A thermoelectric generator module having a new and useful electric insulating film and a method for insulating a thermoelectric generator module are provided. Kind Code: A1 A thermoelectric conversion element module in which a p-type thermoelectric conversion material and an n-type thermoelectric conversion material are alternately connected via electrodes, wherein-(SiH
_A thermoelectric generator module having an electric insulating film, characterized by having an electric insulating film composed of a silica film formed by applying a polysilazane solution or an organopolysilazane solution containing (2NH)-, and insulation of the thermoelectric generator module Method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoelectric element module having a new and useful electric insulating film and a method of insulating the element module.

[0002]

2. Description of the Related Art A thermoelectric conversion element directly converts heat energy into electric power by using a thermoelectric effect (= Seebeck effect) in which a thermoelectric effect is generated between both ends of a thermoelectric conversion element by giving a temperature difference between the both ends. Element. According to the thermoelectric conversion element, two kinds of different metals or different thermoelectric conversion materials such as a p-type semiconductor and an n-type semiconductor are placed in parallel thermally, and the elements are electrically connected in series to load externally. To form a closed circuit, a current flows through the circuit and can be extracted as electric power.

FIG. 1 is a view for explaining the principle of a thermoelectric conversion element. As an example, a combination of a p-type semiconductor and an n-type semiconductor is shown. In FIG. 1, 1 is a p-type semiconductor, 2 is an n-type semiconductor, 3 is a high-temperature side junction, 4 is a low-temperature side junction,
Q indicates a high-temperature heat source, Th indicates a high-temperature side temperature, Tc indicates a low-temperature side temperature, and S indicates an insulating space. The high-temperature side joint 3 is provided with a high-temperature side electrode 5 in common, and the low-temperature side joint 4 is provided with low-temperature side electrodes 6 and 7 separately. When a temperature difference ΔT = Th−Tc is applied between the high-temperature side junction 3 and the low-temperature side junction 4 in the thermoelectric conversion element of this embodiment, a voltage is generated between both electrodes (between 5 and 6 and 7). I do. Therefore, when a load (R) is connected between the two electrodes 6 and 7 on the low temperature side, a current (I) flows and can be taken out as electric power (W).

The electric output W of such a thermoelectric conversion element is expressed by the following equation (1). Here, in the equation (1), I: current,
R: load resistance, S: thermoelectric power, ΔT = Th−Tc, r: internal resistance, m = R / r. As is clear from equation (1), the electric output W greatly depends on the difference (ΔT) between the high temperature side (Th) and the low temperature side (Tc), and is proportional to the square of ΔT.

[Equation 1]

For this reason, the electric output W of the thermoelectric conversion element can be increased by increasing the difference (ΔT) between the high temperature side (Th) and the low temperature side (Tc). For example, the cell temperature during operation of a solid oxide fuel cell is about 7
The temperature is as high as about 00 to 1000 ° C. The temperature of the combustion zone varies depending on the fuel utilization factor and the air utilization factor, and varies depending on the location.
About 000 ° C. When the low temperature (Tc) is room temperature (20
° C), a maximum temperature difference of ΔT = 780 to 980 ° C can be obtained, and a large electric output W can be obtained.

In this type of thermoelectric conversion element, the current obtained is roughly proportional to the number of elements, and the amount of power obtained is proportional to the size of the element. However, the voltage is only several tens mV at most in any case using only a pair of two different thermoelectric conversion materials. In this sense, the thermoelectric conversion element is a small voltage, large current type power supply, and cannot normally obtain a desired voltage. For this reason, in many cases, it is necessary to laminate a plurality of pairs, and several modes have been considered as a technique for this lamination, but FIG. FIG. 4 is a diagram schematically showing one embodiment of the present invention, in which a plurality of pairs of pn units are connected in series as shown in FIG.

As shown in FIG. 2, a plurality of pairs of a p-type semiconductor and n
Type semiconductors are alternately juxtaposed at intervals, and adjacent p-type and n-type semiconductors are connected in series by electrodes. FIG. 2 shows an example in which 59 pn units are connected, but the required number is connected. In FIG. 2, reference numeral 8 denotes a thermoelectric conversion element, 9 denotes an electrode (connection strip), 10 denotes a conductor for extracting electric power, and an arrow (→) denotes a current flow. FIG. 3 shows three pairs taken out.
Each thermoelectric conversion element and the electrode are fixed by an adhesive such as a silver paste. Although the thickness of the adhesive is almost nil, it is shown thick in FIG.

In the power generation system using a thermoelectric conversion element, as described above, a temperature difference ΔT is required between the high-temperature side (junction) 3 and the low-temperature side (junction) 4. It is conceivable to use heat of a high-temperature fluid such as combustion exhaust gas as the high-temperature side. The heating surface is attached to the wall of the low-temperature fluid or metal fins placed in the high-temperature fluid flow path, and the cooling surface is placed on the wall of the low-temperature fluid or metal fins placed in the high-temperature fluid flow path. Pasted. FIG. 4 shows the arrangement,
That is, it is a diagram schematically showing a usage example of the thermoelectric conversion element module.

[0009]

As is apparent from FIG. 4, electrodes are exposed on the heating surface and the cooling surface of the thermoelectric conversion element module. When the electrodes are exposed as described above, the respective thermoelectric conversion elements are short-circuited to each other, and a predetermined performance cannot be obtained. Therefore, it is necessary to electrically insulate both surfaces of the thermoelectric conversion element module by some method. FIG. 5 is a diagram illustrating a case where an insulating film is formed on the high-temperature side electrode surface and the low-temperature side electrode surface.

In this case, in order to obtain a large temperature difference ΔT between the high-temperature side (junction) and the low-temperature side (junction), it is important that the insulating film is as thin as possible and has low thermal resistance. That is, in FIG. 5, the portion indicated by B is a portion of a temperature difference (effective temperature difference) ΔT effective for power generation. In addition to the thickness of both electrodes, the thickness C of the insulating film on each electrode surface
Is added, not only the thickness corresponding to "AB (-means to pull)" including this is wasted, but also
Thermal resistance is generated by the thickness. For this reason, it is necessary to make the insulating film as thin as possible, thereby making it possible to increase the effective temperature difference ΔT by reducing the thermal resistance as much as possible.

As the insulating method, for example, (1) a method of sandwiching an alumina plate, (2) a method of spraying alumina,
(3) a method of depositing a polymer film, (4) a method of depositing a silica film, and (5) a method of sandwiching a Teflon (registered trademark) foil or a Kapton foil are possible. However, in the method of (1) sandwiching an alumina plate, the thermal conductivity of the alumina plate is low (that is, the thermal resistance is large), and the thickness is limited to about 50 μm. Inevitably, the thermal resistance must increase.

(2) In the method of spraying alumina, since the alumina itself is an oxide, the melting temperature is high, so that the spraying process is complicated, and there are problems in cost and practicality. (3) In the method of depositing a polymer film, the polymer film itself has a low melting temperature, at most about 300 ° C., and has no heat resistance. (4) In the method of depositing a silica film, as in the case of (2) above, since the silica itself is an oxide, the melting temperature is high, which complicates the spraying process, and poses problems in terms of cost and practicality. is there. (5) In the method of sandwiching a Teflon foil or a Kapton foil, as in the case of (3), since the Teflon foil or the Kapton foil is a polymer and has a low melting temperature (for example, even a heat-resistant polymer is at most 300 ° C.). Degree) Low heat resistance and high thermal resistance.

The present invention is not limited to the above-mentioned various methods considered as a method for insulating the electrode surface of the thermoelectric conversion element module, but by using a specific compound, it can be used in a wide temperature range from room temperature to 1300 ° C., particularly 600 to 13
In addition to being effective in a high temperature range such as 00 ° C., it has been found that an electric insulating film can be formed extremely thinly and easily on the electrode surface of the thermoelectric conversion element module.

That is, the present invention provides a method for electrically insulating the electrode surface of a novel and useful thermoelectric conversion element module in which a silica film is formed on the electrode surface of the module by using a specific compound, polysilazane or organopolysilazane. An object is to provide a thermoelectric element module insulated by an insulating method.

[0015]

SUMMARY OF THE INVENTION The present invention provides (1) a thermoelectric conversion element module in which a p-type thermoelectric conversion material and an n-type thermoelectric conversion material are alternately connected via electrodes. as a structural unit - (SiH ₂ NH) - to provide a thermoelectric power generating element module having an electrical insulating film, characterized in that it comprises an electrically insulating film made of a silica film formed by coating a polysilazane solution containing.

The present invention relates to (2) a thermoelectric conversion element module in which a p-type thermoelectric conversion material and an n-type thermoelectric conversion material are alternately connected via electrodes, wherein an organopolysilazane solution is applied to the surface of the electrodes. A thermoelectric generator module having an electric insulating film characterized by having an electric insulating film made of a silica film formed by the above method.

The present invention relates to (3) a method for insulating an electrode surface in a thermoelectric conversion element module in which a p-type thermoelectric conversion material and an n-type thermoelectric conversion material are alternately connected via an electrode. as a structural unit - (SiH ₂ NH) - provides a method of insulating the thermoelectric power generating device module and forming an electrical insulating film made of silica film by applying a polysilazane solution containing.

The present invention provides (4) a method for insulating a surface of an electrode in a thermoelectric conversion element module in which a p-type thermoelectric conversion material and an n-type thermoelectric conversion material are alternately connected via an electrode. Provided is a method for insulating a thermoelectric power generation element module, wherein an electric insulating film made of a silica film is formed by applying an organopolysilazane solution.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION A thermoelectric conversion element is composed of two different types of thermoelectric conversion materials, for example, p thermoelectric conversion materials and n thermoelectric conversion materials connected in required numbers. The required number of shaped thermoelectric conversion element pairs are connected via electrodes. As the thermoelectric conversion element in the present invention, any of those thermoelectric conversion elements can be used, and the constituent materials of the thermoelectric conversion element are not limited. In the present specification, two thermoelectric conversion materials, for example, a required number of units of p thermoelectric conversion material-n thermoelectric conversion material connected via electrodes and put together are referred to as a thermoelectric conversion element module.

In the present invention, a polysilazane solution or an organopolysilazane solution is applied to the electrode surface of the thermoelectric conversion element module. The polysilazane used in the present invention is-
It is a polymer containing (SiH ₂ NH) — as a structural unit. The organopolysilazane used in the present invention is a silicon-containing copolymer containing at least structural units represented by the following general formulas (1) to (3). Here, in the following general formulas (1) to (3), R ¹ , R ² , R ⁴ , R ⁵ , R ⁷ and R ⁸
Is each independently an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, an aralkyl group, an alkylamino group or an alkylsilyl group, and R ³ and R ⁶ are each independently a divalent aromatic group. Further, the structural units (1) to (3) are random, and the respective molar ratios p, q and r are such that p / q = 0.01 to 99 and p / r = 0.01 to
Take a 99 relationship.

[Formula 1]

The silicon-containing copolymer may optionally contain a structural unit represented by the following general formula (4) or (5). Here, the following general formulas (4) to
In (5), R ⁹ is an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, an aralkyl group or an alkylsilyl group, and R ³ is the same as described above. The structural units (1) to (5) are random, and the molar ratios p, q, r, m, and n are (m + n) / (p + q) =
0.01 to 99, (m + p) / (n + q) = 0.01 to
99, r / (m + n + p + q) = 0.01-99.

[Formula 2]

In the present invention, the above-mentioned polysilazane or organopolysilazane solution is applied to the electrode surface of the thermoelectric conversion element module, and then left at room temperature or heated to form an electrical insulating film made of a silica film. Is done. As the solvent for polysilazane or organopolysilazane, hydrocarbons such as aliphatic hydrocarbons, alicyclic hydrocarbons, and aromatic hydrocarbons, halogenated hydrocarbons, ethers, alcohols, esters, ketones, and the like can be used. it can. The organopolysilazane can be obtained, for example, by a production method described in JP-A-8-231727. In the present invention, it has been found out that this has excellent performance for electrical insulation of a special specific object such as an electrode surface of a thermoelectric conversion element module, and this is utilized.

FIG. 6 is a view for explaining a step of forming the silica film. A polysilazane solution or an organopolysilazane solution is applied to both electrode surfaces of the thermoelectric conversion element module configured as shown in FIG. 2 or FIG. There is no limitation on the method of application, and for example, the application may be performed using a brush, or may be applied by flow coating. After the application, the silica thin film may be left at room temperature, but preferably heated to form a silica thin film. Although the detailed mechanism of the change from polysilazane or organopolysilazane to silica is not always clear, water in the atmosphere is involved, which causes polysilazane to decompose, generating ammonia, hydrogen, etc., and forming a silica film. Conceivable.

According to the present invention, a silica thin film can be formed on the surface of a thermoelectric conversion element module simply by applying a polysilazane or organopolysilazane solution to the electrode surface and leaving it alone, or by simply heating after application.
Therefore, the forming process is very simple. For this reason, the cost is also excellent. Further, according to the present invention, since the silica thin film can be formed as extremely thin as 1 μm, for example, the thermal resistance can be made extremely small, so that the power generation performance of the thermoelectric conversion element module does not substantially decrease.

In the present invention, the electrical insulating film made of a silica thin film formed on the electrode surface of the thermoelectric conversion element module has excellent heat resistance and thermal conductivity, and has a temperature of 1300 to room temperature.
It is effective over a wide temperature range of
It is effective in a high temperature range such as 00 ° C. For this reason, the thermoelectric conversion element module of the present invention can be used particularly in a high temperature range, for example, about 700 to 1 in the operation of the solid oxide fuel cell.
The present invention can be applied to extracting electric power using a high temperature such as about 000 ° C.

The thermoelectric conversion element module according to the present invention is constructed.
Pb-Te based (PbTe)
Etc.), Bi-Te system (Bi_TwoTe_ThreeEtc.), Co-Sb type
(CoSb _ThreeEtc.), Si-Ge type (Si_0.8Ge
_0.2Etc.), FeSi-based (FeSi_TwoEtc.) intermetallic compounds
It can be used, but this is especially 600-1300 ° C.
When used in a high temperature range such as
An electric conversion material is used. For example, for example:
Complex oxide-based thermoelectric conversion materials such as (1) to (7)
used.

(1) Element composition formula ACoxOy (where A
Is Li, Na or K, x is 1 ≦ x ≦ 2, y is 2 ≦
y ≦ 4), and a thermoelectric conversion material comprising an elemental composition formula (A _Z B _1-Z ) CoxOy, wherein
A is Li, Na or K, B is Mg, Ca, Sr, Ba,
Sc, Y, Bi, or Te, z is in the range of 0 <z <1, x is 1 ≦ x ≦ 2, and y is 2 ≦ y ≦ 4]. JP-A-9-321
346). (2), thermoelectric conversion material containing Mn, Fe or Cu at the Co site of the elemental composition formula (1)
-256612).

(3) Elemental composition formula (Na _P B _1-P ) (Co _Z
A _1-Z ) xOy thermoelectric conversion material [where x is 1 ≦ x ≦ 2, y is 2 ≦ y ≦ 4, p is 0 <p ≦ 1, z is 0 <z ≦ And B or A or B and A are each Ag, Li, lanthanoid, Ti, Mo, W, Z
at least one element selected from r, V and Cr] (JP-A-11-266038). (4) The elemental composition formula _{(Na P B 1-P)} (Co Z A 1-Zq Cu q) thermoelectric material [However Shikichu made of a substance represented by xOy, x is 1 ≦
x ≦ 2, y is 2 ≦ y ≦ 4, p is 0 <p ≦ 1, z and q are 0 <z <1, 0 <q <1, z ≦ 1−q (p is 1 B and A or B and A are one or two selected from Ag, Li, lanthanoid, Ti, Mo, W, Zr, V, and Cr, respectively. Shows the above elements] (JP-A-11-26603)
No. 8). The above (1) to (4) are p-type oxide thermoelectric conversion materials.

[0029] (5) The the In ₂ O ₃ and n-type oxide thermoelectric conversion material mainly, basic composition: the In ₂ O ₃ be doped with at least one tetravalent element against Characteristic n-type oxide thermoelectric conversion material (Japanese Patent Application No. 11-2309)
No. 46). (6) In ₂ O ₃ and an n-type oxide thermoelectric conversion material mainly, basic composition: Zr relative to In ₂ O _3,
An n-type oxide thermoelectric conversion material characterized by being doped with at least one element selected from Sn (Japanese Patent Application No. 11-230946). (7) An n-type oxide thermoelectric conversion material mainly composed of In ₂ O ₃ , which has a formula (In _1−X A _X ) ₂
N-type oxide thermoelectric conversion material represented by O ₃ (where A is one or two elements selected from Zr and Sn, and x = 0.00005 to 0.1) (Japanese Patent Application No. 1
No. 1-230946).

[0030]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but it goes without saying that the present invention is not limited to these Examples.

Example 1 <Formation of Silica Film on Thermoelectric Conversion Element Module> A thermoelectric conversion element module composed of an Al electrode, a p-type Bi-Te type thermoelectric conversion material, and an n-type Bi-Te type thermoelectric conversion material To form a silica film. This thermoelectric conversion element module has a thermoelectric conversion element module (pn
49 unit pairs: size = 6.27 × 6.27 × 0.
5 mm), and the upper and lower Al electrodes are exposed. A high-speed conversion type polysilazane solution (trade name: D110, manufactured by Tonen Corporation, molecular weight (Mn) = 700, solvent = xylene, concentration = 20 wt%, color tone = colorless, viscosity = 1.10.
cp) was applied. This coating was performed by flow coating, that is, by vertically turning the module and flowing the high-speed conversion type polysilazane solution from above. Thereafter, it was kept at 100 ° C. for 1 hour in a thermostat. This coating and post-treatment were performed twice. The thickness of the silica thus formed was about 1 μm.

<Preparation of Thermoelectric Generator> Two thermoelectric conversion element modules, each having the above configuration, are disposed on the upper and lower surfaces of the heat pipe on the cooling side (formed in a plate shape), respectively, for a total of four sheets. A thermoelectric generator having the structure shown in FIG. 7 was assembled. Water cooling fins are arranged on both upper and lower surfaces (on which the silica film is formed) of the thermoelectric conversion element module, and high temperature gas fins are arranged on the heating side of the heat pipe. Although not shown, the fins for high-temperature gas are disposed in a high-temperature gas passage surrounding the fins, and the fins for water cooling are disposed in a cold water passage for water cooling. The heat pipe (made of iron) contains a heat medium (water) in a space therein, and heat is transferred from the high-temperature side to the low-temperature side.

<Measurement of Electromotive Force and the Like> A power generation test was performed using the thermoelectric power generation device prepared above. Heated air was used as the hot gas. A high-temperature gas of 420 ° C. was passed through the high-temperature gas fins, and a water of 20 ° C. was passed through the cooling fins to generate a temperature difference of 400 ° C. on the upper and lower surfaces of the thermoelectric conversion module. At this time, when the open electromotive force was measured, a voltage of about 2.8 V was obtained, and an output of about 36 W was obtained as power.

As a comparative example, a thermoelectric conversion element module in which a Teflon foil (thickness: 20 μm) was sandwiched between both electrode surfaces of a thermoelectric conversion element module manufactured in the same manner as in the above-described embodiment was used as shown in FIG. With respect to the thermoelectric generator configured as described above, electromotive force and the like were measured under the same conditions as above. When the open electromotive force at a temperature difference of 400 ° C. was measured, a voltage of about 2.5 V was obtained, and the power was about 24 W
Was obtained. As is clear from comparison between Example 1 and the comparative example, the remarkable effect of the present invention is clear.

Example 2 Instead of the p-type Bi-Te thermoelectric conversion material and the n-type Bi-Te thermoelectric conversion material in Example 1, Na _0.95 Ag _0.05 C was used as a p-type thermoelectric conversion material.
o ₂ O ₄ as an n-type thermoelectric conversion material (Nd _0.95 Z
with r _{0.05) 2} CuO _4, these eight pairs linked via a Pt electrode to produce a thermoelectric conversion element module, the Pt electrode of the back surface adhered to an alumina substrate by using a Pt paste. Each p-type and n-type thermoelectric conversion material is 3 × 3 × 3
mm in cubic shape, and a Pt lead wire for power extraction is provided at two places of the Pt electrode on the alumina substrate.
Adhered by t paste. 8 is a plan view thereof, and FIG. 9 is a sectional view taken along line XX in FIG.

Using the same high-speed conversion type polysilazane solution used in Example 1, a silica film was formed on the electrode surface of the module surface in the same manner as in Example 1. Using this thermoelectric conversion element module, a thermoelectric generator having the structure shown in FIG. 7 was assembled. An electromotive force was applied in the same manner as in Example 1 except that a high-temperature gas of 800 ° C. was passed through the fin for high-temperature gas, and the cooling fin was air-cooled to generate a temperature difference of 200 ° C. on the upper and lower surfaces of the thermoelectric conversion element module. Were measured. As a result, a maximum value of the open electromotive force of about 400 mV was obtained, and an output of about 169 μW was obtained as the maximum power at this time.

As a comparative example, a 100 μm-thick alumina plate was disposed as an insulating means on the electrode surface on the surface of the thermoelectric conversion element module produced in the same manner as described above, and a thermoelectric generator having the structure shown in FIG. Was assembled, and the electromotive force and the like were measured in the same manner as described above. As a result, a maximum value of the open electromotive force of about 363 mV was obtained, and an output of about 150 μW was obtained as the maximum power at this time. As is clear from comparison between Example 2 and Comparative Example, the remarkable effect of the present invention is clear.

[0038]

The insulating film of the present invention has excellent heat resistance and thermal conductivity and is effective in a wide temperature range from room temperature to 1300 ° C., and is particularly effective in a high temperature range of 600 to 1300 ° C. Further, according to the present invention, a silica thin film can be formed on the surface of the thermoelectric conversion element module simply by applying polysilazane or organopolysilazane to the electrode surface and leaving it alone, or by heating after application. For this reason, the forming process is very simple, and therefore, the cost is also excellent. Further, according to the present invention, since the silica thin film can be formed as extremely thin as, for example, 1 μm, the thermal resistance can be extremely reduced, so that the power generation performance of the thermoelectric conversion element module does not substantially decrease. Excellent effects can be obtained.

[Brief description of the drawings]

FIG. 1 is a view for explaining a thermoelectric conversion element in principle.

FIG. 2 is a diagram showing one embodiment of a thermoelectric conversion element module configured in a flat plate shape.

FIG. 3 is a diagram showing three pairs of p-type and n-type pairs in FIG.

FIG. 4 is a diagram schematically showing a usage example of a thermoelectric conversion element module.

FIG. 5 is a diagram illustrating a case where an insulating film is formed on a high-temperature side electrode surface and a low-temperature side electrode surface of a thermoelectric conversion element module.

FIG. 6 is a diagram illustrating a step of forming a silica film in the present invention.

FIG. 7 is a diagram schematically illustrating a thermoelectric generator used in an example.

FIG. 8 is a diagram (plan view) schematically illustrating a thermoelectric conversion element module according to a second embodiment.

FIG. 9 is a sectional view taken along line XX in FIG. 8;

[Explanation of symbols]

 1, p (P) p-type semiconductor 2, n (N) n-type semiconductor 3 high-temperature side junction 4 low-temperature side junction Q high-temperature heat source Th high-temperature side temperature Tc low-temperature side S insulation space 5 high-temperature side electrode 6, 7 low-temperature Side electrode 8 Thermoelectric conversion element 9 Electrode (connection strip) 10 Conductor for power extraction

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 35/34 H01L 35/34 H02N 11/00 H02N 11/00 A (72) Inventor Tadashi Mochida Tokyo Metropolitan Port 1-5-20 Kaigan-ku, Tokyo Gas Co., Ltd. (72) Inventor Kenjiro Fujita 1-5-20 Kaigan, Minato-ku, Tokyo Tokyo Gas Co., Ltd.

Claims (8)

[Claims] 1. A thermoelectric conversion element module in which a p-type thermoelectric conversion material and an n-type thermoelectric conversion material are alternately connected via electrodes, wherein-(SiH)
_A thermoelectric generator module having an electric insulating film, comprising an electric insulating film made of a silica film formed by applying a polysilazane solution containing (2NH)-. 2. A thermoelectric conversion element module in which a p-type thermoelectric conversion material and an n-type thermoelectric conversion material are alternately connected via an electrode, formed by applying an organopolysilazane solution to the surface of the electrode. A thermoelectric power generation element module having an electric insulating film, comprising an electric insulating film made of a silica film. 3. An electric insulating film made of a silica film, wherein the electric insulating film made of a silica film is formed by heating the coated layer after the application of the solution. 3. A thermoelectric generator module having the electric insulating film according to 2. 4. The thermoelectric conversion element module having the electric insulating film is a thermoelectric conversion element module used in a high temperature range of 600 to 1300 ° C. A thermoelectric generation element module having an electric insulating film. 5. A method for insulating a surface of an electrode in a thermoelectric conversion element module in which a p-type thermoelectric conversion material and an n-type thermoelectric conversion material are alternately connected via an electrode. A method for insulating a thermoelectric power generation module, comprising forming an electric insulating film made of a silica film by applying a polysilazane solution containing (SiH ₂ NH)-. 6. A method for insulating an electrode surface in a thermoelectric conversion element module comprising a p-type thermoelectric conversion material and an n-type thermoelectric conversion material alternately connected via electrodes, wherein an organopolysilazane solution is applied to the surface of the electrodes. A method for insulating a thermoelectric power generation element module, comprising forming an electric insulating film made of a silica film by coating. 7. The method for insulating a thermoelectric generator module according to claim 5, wherein the applied layer is heated after the application of the solution. 8. The thermoelectric conversion element module according to claim 1, wherein
The thermoelectric conversion element module according to any one of claims 5 to 7, wherein the thermoelectric conversion element module is used in a high temperature range of 300 ° C.